Automatic tension device.



F. WENGRAF, AUTOMATIC TENsxoN muse. APPLICATION ULED GCT. 28. i916.

mfmm www@ Nov., 27,191?.

2 SHEETS-SHEET i.

WITNESS F. WENGRAF. AUTOMATIC TENSION DEVICE.

APPLICATION FILDJJCT. 28. I9I6.

2 SHEETS-SHEET ZI A ITU/NVE I Pam-ted. Nov. 27, 191?.

FREDERICK WENGRAF, 0F NEW YORK, N. Y.

AUTOMATIC TENSION DEVICE.

Specification of Letters Patent.

Patented Nov. 27, 1191"?.

Application filed October 28, 1916. Serial No. 128,200.

T0 all whom t may concern.'

Be it known that I, FREDERICK VVENGRAF, a subject of the Emperor ofAustria, residing at New York, in the county and State of New York, havemade a certain new and useful Invention in Automatic Tension Devices, ofwhich the following is a specification.

This invention relates to automatic tension applying devices.

The object of the invention is to provide a simple, eflicient device ofthe class set forth, which is constructed of few standard parts, andwhich is economical to manufacture.

A. further object of the invention is to provide a simple device whichwill automatically apply tension to separated parts,

and which will automatically maintain the same amount of tension on theparts, regardless of the amount of give thereof.

Further objects of the invention will appear more fully hereinafter.

The invention consists substantially in the construction, combination,location, and relative arrangement of parts, all as will be more fullyhereinafter set forth, as shown by the accompanying drawing and finallypointed out in the appended claims.

Referring to the drawings Figure 1 is a sectional plan view of astructure embodying my invention.

Fig. 2, is a sectional view partly in elevation of the'same.

Fig. 3 is a similar view with the tension spring removed.

Fig. l is a sectional view taken onthe line 4 4 Fig. 1, and looking inthe direction of the arrows.

Fig. 5 is a view in elevation of a vehicle tire, and showing oneapplication of the automatic tension device.

Fig. 6 is a sectional view of the non-skid tread employed ,in accordancewith the arrangement shown in Fig. 5.

Fig. 7 is a plan view of the tread shown in Fig. 6.

Fig 8 is a sectional view taken on the line 8-8 Fig. 6.

Fig. 9 is a sectional view of a modified structure embodying myinvention. Y

The same part is designated by the same reference numerals wherever itoccurs throughout the several views.

1n accordance with my invention pro.-

vide a casing 9 in which I mount two arms 10, 11, respectively, whichproject out through the end walls of the casing as shown and one ofwhich is adapted to slide or move lengthwise. rl`he arm 10 is curved orbent while the arm 11 is practically of uniform cross sectional areathroughout, so that the surfaces of the arms come in contact with andbear against each other. The bearing or contacting surfaces of the arms10, 11, are

provided with teeth v12, as shown in Fig. 3, and cut inopiiositedircctions to allow the arms to move toward each other, thatis, in wardly, toward the center of the casing, but to prevent the armsfrom moving away from each other, that is, outwardly or out of thecasing. Each of the arms 10, 11, is provided with a pin 13, to which issecured a tension spring 14, as shown, which spring acts to draw therespective arms toward each other as will be clearly understood.

Each of the arms 10, 11, is also provided at their respective outer endsoutside of the casing 9, with a hook memberl of any desired form,adapted to engage or be connected with the elements 16 uponwhich tensionisdesired to be placed. It is desirable to lock this engagement, and forthis pur pose, although I am not to be limited in this respect, Iprovide a well known form of spring clip 17.

To allow adjustment of the tension device, particularly when the deviceis first applied, I provide a push pin 18, which passes through the wallof the casing 9, and through the stationary arm 11, and which isprovided with a flanged head 19 lying in a recess 20 cut in the bearingor contact surface of thearm 11, as shown in Fig. 3. The head 19 of thepush pin 18 is rounded, as shown, and bears against the teeth 12 of thearm 10. Thus it will be seen that when the push pin 18 is projectedinwardly, by pressure being applied thereto, the arm 10 is forcedsidewise so that its teeth are pushed out of contact with the teeth ofthe arm 11, thereby allowing the arm 10 to be drawn as far outofthecasing 9 as the pin 13 thereof will allow. The spring 20, bearingagainst the arm 10 and the wall of the casing 9, causes the arm 10 toimmediately bear against the arm 11 when the pressure against the pushpin 18 is withdrawn. The hook members 15 arethensecured to the ends, sayof the cable 16to which it is desired to apply tension, and the arm l0is released. The spring 14 will then draw the arm l0 toward the arm 11,the respective teeth thereof presenting no opposition to this directionof movement, due to their direction of cut, but if additional exteriortension is applied to the member 16, tending to separate the arms 10,11, the teeth thereof engage with each other and prevent any movement ofthe arm 10, as is clearly shown.

In Fig. 5, I have shown my device as applied to a non-skid attachmentfor automobile tires, but it will be understood that my invention, asdefined in the claims, is not to be limited to any specific use, as itis obvious that the device may be used in any instance where the slackbetween elements under tension is desired to be automatically taken up.

In the arrangement shown, the tire 21 is provided with two cables 22,one on each side thereof at its base, on which cables are mounted hookmembers 23, preferably provided with clip springs 24, as shown. Thesehook members receive the ends of any desired type of non-skid treadelements, such for instance, as the form designated by reference numeral26. The automatic tensioning device designated at 29, is attached to theends of the cables on each side of the tire.

Thus it will be seen that by employing the automatic tension deviceembodying my invention in connection with any form of non-skidattachment, the slack of the same is automatically taken up, all times atight fit of the parts, thereby eliminating entirely the noise andrattle of loose parts of the non-skid attachments at present employed.Due to the fact that to enable the ready application and removal of thepresent non-skid attachments, they are made comparatively loose, therehas been no effort heretofore to eliminate the noise and rattle causedthereby, but Vwhich is obviously objectionable. Y

While I have shown and describeda specific structure embodying myinvention, Yit will beunderstood that manychanges, in detail, willreadily occur to those skilled in the art, Ywithout departing from thebroad scope of my invention, as defined in the claims. l

Therefore, what I claim as new and useful, and of my Vown invention, anddesire to secure by Letters Patent, is,-

1. A device for maintaining tension, comprising a housing, a stationaryarm and a movable arm located in said housing, means for' yieldinglymaintaining said arms in contact with each other, means tending to drawsaidarms longitudinally toward each other, and means for preventing saidarms frm .being drawn longitudinally from each ot er.

maintaining atk prising a housing, a stationary arm and a movable armlocated in said housing,means for yieldingly maintaining said arms incontact with each other, the respective contact-V ing surfaces of saidarms being provided with oppositely cut-teeth, and means tending to drawsaid arms longitudinallytoward each other, said teeth being adapted topermit said movement, but to prevent longitudinal movement of said armsin the opposite direction.

4. A device for maintaining tension, comprising a stationary arm and amovable arm, means for yieldingly maintaining said arms in contact witheach other, the respective contacting surfaces of said arms beingprovided with oppositely cut teeth, aspring connecting said arms to drawsaid arms longitudinally toward each other, said teeth being adapted topermit said movement, but

to prevent longitudinal movement of said arms in the opposite direction,and meansto yieldingly hold said teeth in engaging relation.

5. A device for maintaining tension, comprising a stationary arm and amovable arm,

means for yieldingly maintaining said arms in contact with each other,the respective contacting surfaces o-fsaid arms being provided withoppositely out teeth, Vmeans tending to draw said arms longitudinally.toward each other, said teeth being adapted to per.- mit said movement,but to .prevent longitudinal movement ofsaidarms in the oppositedirection, and handoperated means for forcing said teeth out ofengagement' to allow longitudinal movement of said movable arm in eitherdirection. f

6. In a device ofthe Aclass described, a casing, a stationary andramovablearmlocatedtherein, extending in opposite longitudinal directions,Vand throughtheends of the casing respectively, Ysaid arms being incontact with each other Vand provided with oppositely cut teeth ontheopposed surfaces thereof, to allow the inwardV movement of saidmovable arm relative to said casing, but to prevent the outward movementthereof,

a spring tending to draw said movable arm if into Vsaid casing, andmeans for yieldingly holding the teeth of said movable arm in contact.with the teeth of said` stationary arm. i 7. In a device of the classdescribed, a

casing, a stationary and a movable arm located therein, extending inopposite longitudinal directions, and through the ends of the casingrespectively, said arms being in contact With each other and providedwith oppositely cut teeth on the opposed surfaces thereof, to allow theinward movement of said movable arm relative to said casing, but toprevent the outward movement thereof, a spring tending to draw saidmovable arm into said casing, and means for yieldingly holding the teethof said movable arm in contact With the teeth of said stationary arm.

8. In a device of the class described, arms disposed in longitudinalrelation to each other and permanently inclosed Within a casing, and oneengaging upon the other, said arms being relatively movablelongitudinally in one direction, and having means to engage each V'otherto prevent relative longitudinal movement in the other direction.

9. In a device of the class described, arms disposed in longitudinalrelation to each other and permanently inclosed Within .a casing, andone engaging upon the other, and means tending to relatively move saidarms longitudinally in one direction, said arms having means to engageeach other to Copies of this patent may be prevent relative movement inthe other direction.

10. In a device of the class described, arms disposed in longitudinalrelation to each other and permanently inclosed Within a casing, and oneengaging upon the other, said arms being relatively movablelongitudinally in one direction, and having means to engage each otherto prevent relative longitudinal movement in the other direction, incombination with a cable having its ends connected to the outer ends ofsaid arms.

11. In a device of the class described, arms disposed in longitudinalrelation to each other and permanently inclosed Within a casing, and oneengaging upon the other, said arms being relatively movablelongitudinally in one direction, and having means to engage each otherto prevent relative longitudinal movement in the other direction incombination with a cable having its ends detachably connected to theouter ends of said arms.

In testimony whereof l have hereunto set my hand on this 16th day ofctOber, A. D., 1916.

FREDERICK WENGRAF.

Commissioner of Patents,

Washington, D. C."

